Dynamic Assignment of Frequency Hopping Sequences in a Communication Network

1. A method, comprising: determining a topology of nodes in a network; assigning a plurality of frequency hopping sequences to the nodes based on the topology such that each node of a particular certain set of the nodes is assigned a particular frequency hopping sequence of the plurality of frequency hopping sequences on which to transmit that is different than frequency hopping sequences of neighbors and hidden neighbors of each node of the particular certain set of the nodes, wherein receivers are adapted to listen for transmissions on all frequency bands; and notifying the particular certain set of the nodes of the particular assigned frequency hopping sequence.

2. The method as in claim 1 , further comprising: assigning a second frequency hopping sequence of the plurality of frequency hopping sequences to each node of a second set of the nodes, the second frequency hopping sequence being different than frequency hopping sequences of neighbors and hidden neighbors of each node of the second set of the nodes; and notifying the second set of the nodes of the assigned second frequency hopping sequence.

3. The method as in claim 1 , wherein there are a certain number of frequency hopping sequences to assign, the assigning comprising: assigning all but a particular one of the number of frequency hopping sequences in succession; and assigning the particular one frequency hopping sequence to nodes not already having an assigned frequency hopping sequence.

4. The method as in claim 1 , further comprising: ranking the nodes based on traffic at the nodes; ordering the nodes in a list based on the ranking; assigning an unassigned particular frequency hopping sequence of the plurality of frequency hopping sequences to a highest ranked node in the list not previously having been assigned a frequency hopping sequence; assigning the unassigned particular frequency hopping sequence to a next node in the ordered list that is not a neighbor and is not a hidden neighbor of the highest ranked node; and continuing to assign the unassigned particular frequency hopping sequence to any subsequent nodes in the list that are not a neighbor and are not a hidden neighbor of any node previously assigned to the particular frequency hopping sequence.

5. The method as in claim 4 , wherein ranking is based on one or more traffic characteristics selected from a group consisting of: a number of neighbors of the node; a number of neighbors and hidden neighbors of the node; a number of child nodes of the node in a directed acyclic graph (DAG), an amount of average traffic at the node; an amount of current traffic at the node; an amount of expected traffic at the node; and a priority of the traffic at the node.

6. The method as in claim 4 , further comprising: reaching a last unassigned frequency hopping sequence; and assigning the last unassigned frequency hopping sequence to all nodes in the list not previously having been assigned a frequency hopping sequence.

7. The method as in claim 4 , further comprising: assigning a last unassigned frequency hopping sequence; and in response to nodes remaining in the list that have not previously been assigned one of the plurality of frequency hopping sequences: assigning a particular previously assigned frequency hopping sequence of the plurality of frequency hopping sequences to a highest ranked node in the list not previously having been assigned a frequency hopping sequence; assigning the particular previously assigned frequency hopping sequence to a next node not previously having been assigned a frequency hopping sequence in the ordered list that is not a neighbor and is not a hidden neighbor of the highest ranked node; and continuing to assign the particular previously assigned frequency hopping sequence to any subsequent nodes not previously having been assigned a frequency hopping sequence in the ordered list that are not a neighbor and are not a hidden neighbor of any node previously assigned to the particular frequency hopping sequence.

8. The method as in claim 1 , wherein the frequency hopping sequences of the plurality of frequency hopping sequences are each orthogonal to every other frequency hopping sequence of the plurality of frequency hopping sequences in the network.

9. An apparatus, comprising: one or more network interfaces to communicate with nodes in a network; a processor coupled to the network interfaces and adapted to execute one or more processes; and a memory configured to store a process executable by the processor, the process when executed operable to: determine a topology of the nodes in the network; assign a plurality of frequency hopping sequences to the nodes based on the topology such that each node of a particular certain set of the nodes is assigned a particular frequency hopping sequence of the plurality of frequency hopping sequences on which to transmit that is different than frequency hopping sequences of neighbors and hidden neighbors of each node of the particular certain set of the nodes, wherein receivers are adapted to listen for transmissions on all frequency bands; and notify the particular certain set of the nodes of the particular assigned frequency hopping sequence.

10. The apparatus as in claim 9 , wherein there are a certain number of frequency hopping sequences to assign, the process when executed to assign being further operable to: assign all but a particular one of the number of frequency hopping sequences in succession; and assign the particular one frequency hopping sequence to nodes not already having an assigned frequency hopping sequence.

11. The apparatus as in claim 9 , wherein the process when executed is further operable to: rank the nodes based on traffic at the nodes; order the nodes based on the ranking in a list stored in the memory; assign an unassigned particular frequency hopping sequence of the plurality of frequency hopping sequences to a highest ranked node in the list not previously having been assigned a frequency hopping sequence; assign the unassigned particular frequency hopping sequence to a next node not previously having been assigned a frequency hopping sequence in the ordered list that is not a neighbor and is not a hidden neighbor of the highest ranked node; and continue to assign the unassigned particular frequency hopping sequence to any subsequent nodes not previously having been assigned a frequency hopping sequence in the list that are not a neighbor and are not a hidden neighbor of any node previously assigned to the particular frequency hopping sequence.

12. The apparatus as in claim 11 , wherein node rank is based on one or more traffic characteristics selected from a group consisting of: a number of neighbors of the node; a number of neighbors and hidden neighbors of the node; a number of child nodes of each node in a directed acyclic graph (DAG), an amount of average traffic at the node; an amount of current traffic at the node; an amount of expected traffic at the node; and a priority of the traffic at the node.

13. The apparatus as in claim 9 , wherein the frequency hopping sequences of the plurality of frequency hopping sequences are each orthogonal to every other frequency hopping sequence of the plurality of frequency hopping sequences in the network.